A majority of diseases arise within luminal organs such as the coronary arteries and the gastrointestinal tract. Understanding and diagnosis of these diseases can require knowledge of their gross, microscopic, and compositional structure.
An optical imaging catheter has become an important tool to assess and diagnose diseases arising from luminal organs. Since many of the mechanisms involving diseases occur on a microscopic scale, high-resolution imaging and spectroscopy techniques have become relevant. An important technique for high-resolution imaging is optical coherence tomography (OCT) and/or frequency domain imaging (OFDI) modalities, where rotationally scanning catheters can be used for studying the cross-sectional and three-dimensional microstructure of luminal tissues. In addition, absorption spectroscopy in conjunction with rotationally scanning catheters can be used to obtain the compositional content of luminal tissues. However, all of these techniques provide information at a maximum depth of about 1-2 millimeters. Therefore, a method to perform optical imaging of structures located at greater depths would be valuable.
Accordingly, there may be a need to address at least some of the above-described deficiencies.